RNA interference (RNAi) is expected to be applied to the treatment of disease since it is able to inhibit the expression of specific genes. At the current level of technology, transfection agents used when transfecting cells with small interfering RNA (siRNA) consist mainly of cationic phospholipids that have been indicated to be toxic.
However, when considering the application of siRNA and other nucleic acid pharmaceuticals in the clinical setting, transfection agents are desired to have as low toxicity as possible, and the development of a transfection agent having lower toxicity has been awaited.
Peptide surfactants are known to have an action that stabilizes membrane proteins such as the G protein coupled receptor, bovine rhodopsin, and be capable of self-assembly (Non-Patent Documents 1 and 2). However, their application as transfection agents has heretofore been unknown.
Non-Patent Document 1: Zhao, X. et al., PNAS, Vol. 103, No. 47, 17707-17712
Non-Patent Document 2: Nagai, A., et al., J. Nanosci. Nanotechnol., Vol. 7, No. 7, 1-7